Phonograph-record.



T. A. EDISON.

PHONOGRAPH RECORD.

APPLIOATION FILED JAN. 20, 1912.

Patented Sept. 29, 1914.

( IT D STATES PATENT OFFIGE.

THOMAS EDISON, OF WEST DRANGE, NEW JERSEY, ASSIG-NOR TO NEW JERSEY PATENT COMPANY, 01 WEST ORANGE, NEW JERSEY, A CORPORATION OF NEW JERSEY,

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Patented Sept. 29, 1914.

Application filed January 2b, 1812. Serial No. 672,397.

To all whom it may concern Be it known that I, THOMAS A. EDISON, a citizen of the'United States, and a resident of Llewellyn Park, West Orange, in the county of Essex and State of New Jersey,

have invented certain new and useful 1111- provements in Phonograph-Records, of which the following is a description.

My invention relates to phonograph purity. It has been common to provide records with surface films or veneers of hard materials such as celluloid; but the reproduction from these records has usually been accompanied by harsh unpleasant scratchy sounds which I'have discovered to, be due to the fact that the 'record surface is hard and unyielding so that the reproducer strikes the bottom of the record groove with a more 1 or less sharp blow. In order to overcomethis and other objections and at the same time provide a Wear resisting surface for the record, I construct my improved record of a flexible or yielding surface film or veneer of hard material, such as a thin sheet of celluloid, and provide a resilient or yielding backing therefor, this backing being in my. preferred construction formed of a base of hard material, such as plaster of Paris, and

a thin film or layer of resilient material such as rubber, intermediate said surface veneer and base. The resilient material should be a substance, such, for example, as rubber,

which yields but is not liable to permanent deformation under the pressure of the re producer stylus.- The resiliency of the intermediate film or layer permits a slight flex .ing or yielding of the surface film or veneer waves on the record surface are transmitted with full amplitude to the reproducer diaphragm. It is understood that the'intermediate film above referred to-yields only sufficiently to permit the cushioning of the stylus so as to eliminate the harsh sounds referred to above.

Other objects of my invention will appear more fully in the followingspec'ification and appended claims.

In order that my-in-vention' may be more fully understood, attention is hereby d1- rected to the accompanying drawings forma ing a part of this specification and in which- Figure 1 represents a central vertical sectional view of a cylindrical sound record embodying my invention; and Fig, 2 represents a similar view of a disk sound record embodying my invention.

Referring to the drawings and more particularly to Fig. 1, the reference numeral 1 indicates a cylinder .of hard material such as celluloid, this cylinder being formed at its ends with inwardly directed flanges and 3. The cylinder 1 is covered on the interior thereof with athin coating 4 of resilient material, such as rubber, this coating being preferably applied by rotating the cylinder 1 and applying a solution of the resilient material, as with -a brush, to the interior or bore of the cylinder. When rubber is used, I prefer to employ a. solution of thesame in benzol. Afterthc layer or film 4: has been allowed to dry, I form on the interior thereof, as by casting, a backing 5 of hard unyielding material, such as plaster of 'Paris. In carrying out the casting operation in practice, I place within the coated cylinder 1. a core having a' recess or groove opening at one end and in thelateral surface of the core, and pour the material to "be-cast into this recess or groove, from which it is led into the annular space between the core and the film 4:. The recessed core does not form apartof the present invention. The base 5 is dried by placing the record within an oven, after which the record may be reamed and otherwise suitably finished. ractice, the core is preferably slightlywit drawn before the base 5 is dried so as to prevent the formation of an. objectionable projection within the bore of the record at .and the base thereto.

base 5. The record impression-is referably formed on the surface of the eel uloid film 1 prior to the'application of the yielding film In order to-produce best results, the film or veneer 1 should be sufficiently thin to be flexible or yielding and the film 4 should be of such a thickness as to cushion; the sharp.

' sudden movements of the reproducer stylus which produce the harsh sounds referred to above withoutcausing such a flexing or yielding of the surface veneer as to appre ciably decrease'the volume of sound emitted during the reproducing of the record. In practice, Ihave found that a suitable thick ness for the celluloid surface film is about .018" and thatasuitable thickness for the intermediate film of rubber is about .0015.

Referring to Fig. 2, the numerals 1, L.

and 5 indicate respectively the hard surface or veneer, yielding intermediate film,

5 hand hard base of a disk record constructed I in accordance with my invention. The

veneer 1 and film 2, as in the form of my invention described above are preferably formed respectively; of celluloid and rubber.

' "F or the'disk sound records, however, I prefer to provide a base not only of considerable hardnessbut also of considerable toughness.

and capable of adhering firmly to the interq mediate film. Suitable materials for such a'base are hard rubber or the phenolic. condensation products which form the subject matter of applications of Jonas W. -Ayls-- Worth, Serial Nos." 496,060, 543,238 and 604,982. With-athedisk record as with the cylindrical record, the record impression should be formed in the surface veneer prior to the application of the flexible film and base thereto.

Rrecord may beof less thickness than that for .the cylindrical record preferably about .005

of an inch in thickness, the yielding film 4 being preferably of substantially the same thickness asthe'corresponding film the cylindrical record, 71. a. about .0015.

I have found in practice that the employment of the yielding intermediate-film referred to above not only improves the quality of therecord but also decreases the wear of the stylus on therecord'and thereby materially increases the life thereof,the hard unyieldingbase preserving the loudness and distinct-ness of the record. Various materials otherthan those specified abovei maybe used by me and numerous other modifications may be made within the scope of my invention.

. What I claim as new and desire to tect byLetters Patent is as follows 1. Asa new article ofmanufacture, a record tablet having a, yielding surface veneer of hard material, and a backing therefor comprising a iha'rd substantially unyielding base and'a layer of resilient material located The celluloid for the disk,

pro-

intermediate said surface veneer and base, said resilient material being yieldable but not liable to permanent deformation under thepressure of the reproducer stylus, sub; stantially as described.

2. As a new article of manufacture, a rec- -ord tablet havinga yielding celluloid surface veneer, and a backing therefor comprising ahard substantially unyielding-base and a layer of resilient material located interme diate said surface veneer and base, said resilient material being yieldable but not liable to permanent deformation under the pressure of the reproducer stylus, substantially as described.

' 8. As a new article of-manufacture, a record tablet having a yielding surface veneer ofhard material, and a backing therefor comprising a hard unyielding base. and a layer of rubber located intermediate said surface veneer and base,.substantially as,described.

4. Asa new article of manufacture, a rec- I ord tablet having a yielding celluloid surface veneer, and a backing therefor comprising a hard unyielding base and a layer of rubber located intermediate said surface veneer and base, substantially as described.

5. As a new article of manufacture, a record tablet. having a yielding surface veneer of hard material, and a backing therefor comprising a plaster base and a layer of resi lient material located intermediate said surface veneer and base, said resilient ma- :terial being yieldable but not liable to per- "manent deformation under the pressure of the reproducer stylus, substantially as described.

6. As a new article of manufacture, a record tablet having a yielding celluloid surface veneer, and abacking therefor comprising a plaster base and a layer of resilient material located intermediate said surface veneer'and base, said resilient material being yieldable but not liable to permanentcomprising a plaster base and a layer of A rubber located intermediate said surface ve- .neer and base, substantiallyas described. 9. As a new article of manufacture, a record tablet having a yielding surface veneer I r of] hard material, and a backing therefor comprising a hard unyielding base and a layer of rubber located intermediate said surface veneer. and base, said veneer being.

less than .025 inches and said layer less than .002 inches in thickness, substantially as described.

10. As a new article of manufacture, a record tablet having a yielding celluloid surface veneer, and a backing therefor comprising a hard unyielding base and a layer of rubber located intermediate said surface veneer and base, said veneer being less than .025 inches and said layer less than .002 inches in thickness, substantially as described.

11. As a new article of manufacture, a record tablet having a yielding celluloid surface veneer, and a backing therefor comprising a plaster base and a layer of rubber located intermediate said surface veneer and base, said veneer being less than .025 inches and said layer less than .002 inches in thickness, substantially as described.

- 12. As a new article of manufacture, a record tablet having a yielding surface veneer,

of hard material, and a backing therefor comprising a hard unyielding base and a layer of rubber located intermediate said surface veneer and base, the thickness of said veneer being approximately .018 inches and the thickness of said layer. approximately .0015 inches, substantially as described.

13. As a new article of manufacture, a record tablet having a yielding celluloid surface veneer, and a backing therefor comprising a hard unyielding base and a layer of rubber located intermediate said surface veneer'and base, the thickness of said veneer being approximately .018 inches and the thickness of saidlayer approximately .0015 inches, substantially as described.

14:. As a new article of manufacture, a record tablet-having a yielding celluloid surface 7 veneer, and a backing therefor comprising a laster base and a layer of rubber located lntcrmediate said surface veneer and base, the thickness of said veneer being approximately .018 inches and the thickness of said layer, approximately .0015 inches, substantially as described.

This specification signed and witnessed this 19th day of J anuar 1912.

TH S. A. EDISON. Witnesses:

FREDERICK BACHMANN, ANNA R. KLEHM. 

